You can use any software to add the signature, as long as it looks reasonably like the template. ;-)
Notice that you can easily use AviSynth to trim the start and end of video files and add fadein/fadout effects.
I use that extensively to merge my recording sessions.
The trimming part is described in this FAQ
The Fade functions are described in the AviSynth wiki
, but I can give you an additional example if you wish.